Published
How long do your locate marks stay valid? Four weeks of life, and a three-week clock underneath.
The rule, in the statute’s own words
A locate ticket is not a one-time purchase — it is a perishable one. Idaho’s Dig Law puts an expiry on the marks themselves, and it is shorter than most schedules assume:
“Unless otherwise agreed in writing by the parties, maintained markings shall be valid for purposes of the notified excavation for a period of no longer than four (4) consecutive weeks following the date of notification as long as it is reasonably apparent that site conditions have not changed so substantially as to invalidate the markings. If excavation has not commenced within three (3) weeks from the original notice to underground facility owners through the one-number notification service, the excavator shall reinitiate notice in accordance with this section.”
— Idaho Code § 55-2205(2). Retrieved 11 September 2026
Four weeks is the wall. Three weeks is the trap. The four-week validity is the outer limit everyone remembers; the three-week commencement trigger underneath it is the one that actually catches jobs, because it fires on a start date, not an end date — and it fires even when the paint still looks fresh.
Two clocks, one ticket
The section runs two separate timers off a single date — the day you gave notice — and they measure different things:
| Clock | Runs from | What it does |
|---|---|---|
| The 3-week commencement clock | The original notice | If excavation has not commenced within three weeks, the excavator must reinitiate notice — even if the marks are intact and the four weeks are not up |
| The 4-week validity clock | The date of notification | Maintained markings stay valid no longer than four consecutive weeks, and only while site conditions have not changed so substantially as to invalidate them |
Read together they say something plain: a ticket is built for a job that starts on time. Push the start past three weeks and the law wants a fresh notice; run past four and the marks are invalid regardless. How much notice to give in the first place — the two-to-ten-business-day window — is covered on the 811 page; this page is about what happens after the marks go down.
Maintaining the marks is the excavator’s job
The sentence immediately before the quote assigns the upkeep: “Once marked … the excavator is responsible for maintaining the markings.” Not the utility, not the locate service — whoever is digging.
- Paint is temporary by design. Weather, traffic, mowing, and construction activity all eat at marks; the statute’s answer is a maintenance duty on the dig side, not a repaint promise from the utility side.
- Validity attaches to maintained marks. The four weeks belong to markings that still exist and still line up with what is buried — which makes the refresh call a judgment call you make early, not late.
- A faded line is not a legal line. Half-visible paint under spoil or snow is the classic mid-job failure, and it is the one late-season digging makes routine.
“Unless otherwise agreed in writing”
The four-week figure is the default, not physics. The parties — the excavator and the facility owner — can agree otherwise, but the statute requires that agreement to be in writing. A verbal “eh, keep digging” from a utility rep is worth exactly what it sounds like it is worth. If a job legitimately needs a longer runway on an existing ticket, get the extension on paper before the clock runs out, with a name on it.
What “commenced” means — and what the statute leaves open
The three-week trigger turns entirely on one word: commenced. The statute does not define it. Does mobilizing equipment count? Staking? The first bucket of topsoil?
The honest answer is that the statute does not say, and this page will not invent a definition. The safe reading is the conservative one — tie the ticket to the day excavation actually begins — and the practical habit is to schedule the notice against the dig start rather than the permit date or the mobilization date. On a job that slips for weather, a machine, or a permit, the locate is the thing everyone forgets to redo; the three-week clock exists precisely for that job.
The permit side: why § 55-2209 gets confused with this rule
People often cite the wrong section for ticket life — usually § 55-2209 — because that section is also about timing and permits. What it actually does is bind public agencies that issue excavation permits: they must notify permit-seekers of the Dig Law and the one-number service, and:
“A permit shall not be valid for excavation until or unless the notice provisions of this section have been complied with… The issuing public agency shall reinstate the permit at no charge within forty-eight (48) hours of receiving evidence of compliance.” — § 55-2209
Which means the county cannot lawfully let you dig on its permit without the locate notice behind it. Skip the notice and the excavation portion of the permit is not valid — and once you cure it, the agency must reinstate at no charge within forty-eight hours. For a county that also requires its own grading and excavation permit for dirt work, the two layers stack: state notice duty, county permit, and the clocks above all running on the same job.
Running a ticket through an Island Park schedule
- Write the notification date on the calendar the day the ticket is issued — both clocks run from it.
- Schedule the excavation start inside three weeks of that date; if the start slips, plan the re-notice before it does.
- Keep the marks usable — the maintenance duty is the excavator’s, and validity belongs to maintained markings.
- Watch the conditions clause: new fill, grading, or storm changes that plainly invalidate the marks end them early.
- Treat four consecutive weeks as the absolute wall, and get any extension in writing, with a name on it.
- If a county permit is in the file, remember its excavation portion is not valid without the notice — cure any gap and the agency reinstates at no charge within 48 hours.
- When the schedule is honest about the clocks, the dig starts the day it is supposed to — (208) 932-1140.
Common questions
How long are 811 locate marks valid in Idaho?
No longer than four consecutive weeks following the date of notification, unless the parties agree otherwise in writing — and only as long as it is reasonably apparent that site conditions have not changed so substantially as to invalidate the markings.
When do you have to call 811 again?
If excavation has not commenced within three weeks of the original notice, the excavator must reinitiate notice — a trigger that fires on the start date even when the marks are still fresh and the four weeks are not up.
Whose job is it to keep the locate marks fresh?
The excavator's. Idaho Code § 55-2205(2) says that once marked, the excavator is responsible for maintaining the markings — the utility's obligation ends at marking them.
Can the four-week validity be extended?
Only by written agreement between the parties. The statute's default can be altered, but the alteration has to be in writing — a verbal assurance does not extend a ticket.
What invalidates locate marks early?
Site conditions changing so substantially that it is reasonably apparent the markings no longer hold — new fill placed over the area, regrading, washouts, or anything else that moves the ground the locator walked.
Does mobilizing equipment count as commencing excavation?
The statute does not define "commenced." The safe reading ties the three-week clock to the day excavation actually begins, and schedules the notice against that date rather than mobilization.
Is the second 811 call free?
Yes — the locate service costs the property owner nothing, which is why a re-notice is the cheapest schedule correction on any job that slips. The notice window itself is covered on this site's 811 page.
What does Idaho Code § 55-2209 actually say?
It governs public agencies that issue excavation permits: they must notify permit-seekers of the Dig Law and the one-number service, a permit is not valid for excavation until the notice provisions are complied with, and a suspended permit is reinstated at no charge within 48 hours of evidence of compliance.
Do homeowners follow the same validity clocks?
The clocks sit on the excavator — whoever is doing the excavation. On an owner-run job that is the owner, which is why both the notice window and the expiry rules apply to do-it-yourself digs the same way.
What about marks under snow late in the season?
Snow is the condition that erases marks while the job waits. Late-season digging pages on this site cover the schedule side; the statute's side is simple — invalid or unmarked means re-notice before the machine works.